四分律比丘含注戒本 2.315

2.315

The Buddha was in Śrāvastī. A woman was about to return to her husband's home, and because she prepared food and repeatedly gave it to the bhikṣus, the time elapsed without her returning, and when her husband returned, he took another wife. Moreover, there were traveling merchants whose food was given repeatedly in portions, and they were consequently robbed by bandits. The bhikṣus reported these faults to the Buddha, and on that account he formulated the precept.